Statins May Reduce Dementia Risk By 70 Percent

People over the age of 50 who are prescribed cholesterol-lowering drugs known as
statins may reduce by 70 percent their risk of developing dementia.

Researchers, Dr. Hershel Jick and colleagues from the Boston Collaborative Drug
Surveillance Program, Boston University School of Medicine, in collaboration
with Dr David Drachman, the University of Massachusetts Medical School,
acknowledged the immediate impact with publication of their epidemiological
study of the potential effect of statins and other lipid-lowering agents (LLAs)
on dementia.

Dr. Jick said of their report: "If substantiated, the implications of this
observational study are considerable. These findings suggest that the use of
statins could substantially reduce the risk of dementia in the elderly, either
by delaying its onset, or by opposing specific or general age-related changes
that result in cognitive impairment.

"We are aware of the substantial potential consequences of this
publication, and that our data should be replicated by additional studies. Given
the potential impact of this study, additional studies of acceptable quality are
urgently needed."

Researchers point out that dementia affects an estimated 10 percent of people
over the age of 65. Vascular and lipid-related mechanisms are thought to have a
role in the pathogenesis of Alzheimer's disease and vascular dementia.

Using a nested case control study based on information gathered from 388 family
practices in the British-based General Practice Research Database, an
epidemiological study was made of the potential effect of HMGCoA (3
hydroxy-3methylglutaryl-coenzyme A) reductase inhibitors (statins) and other
lipid-lowering agents on dementia.

The base study population included three groups of patients aged 50 and over who
had received lipid-lowering agents (LLAs), and who had a clinical diagnosis of
untreated hyperlipidaemia plus a randomly selected group of other patients.

All cases with a clinical diagnosis of dementia were identified from this base
population. Each case was matched with up to four controls derived from the base
population for age, sex, practice, and index date of case. The study encompassed
284 cases with dementia and 1 080 matched controls.

Among controls, 13 percent had untreated hyperlipidaemia, 11 percent were
prescribed statins, seven percent received other LLAs, and 69 percent had no
hyperlipidaemia or LLA exposure.

Patients prescribed statins were around 70 percent less likely to have dementia
compared with people who had no diagnosis of hyperlipidaemia or exposure to
other lipid-lowering drugs. Patients treated with other LLAs, and individuals
with untreated hyperlipidaemia, did not have a significantly reduced risk of
dementia.

"We determined the relative risk for dementia in the group diagnosed as
'dementia' as compared with those diagnosed as 'Alzheimer's disease', and found
no material difference in effect," Dr. Jick and his collaborators report.
"This suggests that there may be a common risk factor for dementia related
to the effect of statins."